There are various types of guns classified as simulation guns, which have been changing from leisure pursuits. The change is considered to be accompanied by results that the simulation guns are very safe for not using gunpowder and development of the simulation guns of high quality and high precision is evaluated. As means for complementing real guns, the simulation guns are in wide use for the purpose of a drill and the like in police and the Self-Defense Forces. As simulation guns suitable for this purpose, there are gas guns using compressed gas, air guns using compressed air generated by a piston cylinder mechanism, and the like. The air guns include electric guns operated by an electric mechanism in addition to manually operated guns.
In electric guns, a piston cylinder mechanism is driven by an electric motor serving as a power source. As a result, a bullet is shot with generated compressed air. Such electric guns have been improved based on the invention relating to an automatic air gun that is disclosed in JP-A-3-221793 (JP-B-7-43238) and is developed by the applicant of this application. The electric gun according to the aforementioned invention has a configuration as follows. Bullets are supplied during a series of operations. There is provided a bullet supply port 7 for supplying bullets one shot at a time from the side to a bullet supply chamber in front of an air-blast port provided in a cylinder. Meanwhile, a shutter that opens and closes the bullet supply port 7 is disposed so as to be able to reciprocate. An engagement portion is provided on the rotary gear which is separated from a rotary shaft of the gear by a certain radius, and engagement means engaging with the engagement portion, and the shutter are linked by a slide arm. The slide arm is biased in a slide direction by a spring.
In this manner, in the electric guns, since the bullet supply port is open by being interconnected to the piston cylinder mechanism, an open time of the bullet supply port is merely a short moment during one rotation of the rotary gear. Due to the configuration, one bullet being pushed from a magazine in a bullet supply direction can be sent through the bullet supply port. However, in a case of a simulation gun having a form different from that described above, there are cases where the open time which can be acquired through a method in the related art is not sufficient for sending all the bullets to the bullet supply port. For example, in an electric gun including an electrically operated compressed air generating unit that has a plurality of barrels and blasts each bullet with air in order to shoot the bullet disposed in a cartridge portion of each barrel, since there is one passage for the bullet to be supplied to the cartridge portion of each barrel, a time corresponding to the number of barrels is required in supplying bullets.
In order to lengthen the open time for the bullet supply port, there is a method of taking a long retracting time of a nozzle. As an example thereof, JP-A-2007-120920 (Japanese Patent No. 4745021) discloses an invention which relates to a nozzle portion driving mechanism. However, in this invention, due to the restriction that a sector gear has to be reduced in size, an attempt is made by adjusting the length of a second teeth in a rotations direction. Although there is no problem when supplying one bullet, it becomes difficult to cope with a case of supplying a plurality of bullets. Moreover, since the nozzle has a structure being integrated with a tappet member, when the stroke of the tappet member becomes long, the moving distance of the nozzle also has to be long. Therefore, the nozzle is also increased in size, resulting in a problem of a space and a problem of a loss during compression, for example, an extended time for generated compressed air to reach the bullet in the cartridge portion. In a case of using bullets of 6 mm, that is, so-called airsoft pellets, the simulation gun is regulated by the regulations such as Article 1-2 in the Firearms and Swords Control Act prohibiting kinetic energy at a particular point of measurement from exceeding 3.5 J/cm2. The aforementioned problems are not an obstacle when complying with the relative regulations. However, when power is weakened more than necessary, it is no longer attractive as a product and is not preferable. Products ought to satisfy the required demands at all times.